<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>登录</title>
<script>
  function inspect() {
    var usr = document.frm.usr.value;
    var pwd = document.frm.pwd.value;
    return (usr != "" && pwd != "");
  }
</script>
</head>
<body>
  <div style="text-align: center">
    <form name="frm" action="login" method="post">
      <fieldset>
        <legend>登录</legend>
        <label>身份<input type="text" name="usr"></label><br>
        <label>密码<input type="password" name="pwd"></label><br>
        <input type="submit" value="登录" onclick="return inspect()">
      </fieldset>
    </form>
  </div>
</body>
</html>